Rihanna's big night out in London ended with a bloody knee that may or may not have been indirectly caused by Chris Brown.

On Saturday night, the minidress-clad chanteuse was reportedlypartying at hot spot The Box with model Cara Delevingne when someone hurled a bottle of energy drink Lucozade in her direction, along with a few choice words about her sometime squeeze, Chris Brown.

While the bottle didn't connect, the resulting tumult apparently caused RiRi to fall against the grate of a shop window and scrape her knee (see photo below). No word on whether the alleged Brown-related insults hit the mark.

The injury, such as it was, seemed to need only a bit of disinfectant and perhaps a SpongeBob-themed Band-Aid.

RiRi is in London for Fashion Week and had just presented her debut collection for British retailer River Island before the club kerfuffle.